Internal-combustion engine.



110.861,711. PATBNTED 11111130, 19o?.

INTERNAL GMBUSTON ENGINE.

APPLIOATIGN FILED 0014. 1906.

3 SEEETS-SHEET l.

No. 861,711. PATENTED JULY 30, 1907.

J. GROPT.

INTERNAL GOMBUSTION ENGINE.

APPLICATION FILED ooTA. 190e.

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PATENTED JULY 30, 1907.

J. GROPT. INTERNAL GOMBUSTION ENGINE.

APPLICATION FILED OOTA, 1906.

3 SHEETS-SHEET 3.

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WVVNESSES;

ATTORN ET.

' next charge is drawn in.

I UNITED STATES PATENT OFFICE.

JOHN CROFT, OF BIRMINGHAM, ENGLAND, ASSIGNOR OF THREE-FOURTHS TO BENJAMIN JAMES BROADWAY, WILLIAM LINGHAM BROADWAY, AND JOSEPH BANNER BROADWAY,

OF BIRMINGHAM, ENGLAND.

INTERNAL-GOMBUSTION ENGINE.

Specification of Letters Patent.

Patented July 30,1907.

Application filed 00550119? 4, 190B. Serial No. 837,401.

To all whom it may concern: r

Be it known that I, JOHN Caor'r,I a subject of the King of Great Britain, residingat 13] Great Hampton street, Birmingham, in the county of Warwick, England, manufacturer, have invented certain new and useful Improvements in Internal-Combustion Engines, of which the following is a specification.

The invention consists of internal` combustion Aengines and has for its object the construction of an engine with a higher eiiciency which is more regular and silent in its working, easier in its control and in which the liability to back firing is practically entirely obviated. The engine ismoreover very simple in its construction and may? allow-of the induction valve and exhaust and operating mechanism being dispensed with.

The improvements are particularly intended to be applied to engines of the type receiving an impulse every revolution but may also be applied to engines receiving an impulse every two revolutions. In this type the petroleum vapor is led into the crank case from which it passes to the cylinder head or combustion chamber by a side passage under impulse from the piston.

With the object of conserving the power and fuel a passage is arranged from the compression space of the cylinder back to the crank case with a control from the handle bar steering post, or other convenient position, so that when on less than full power a portion of the gases may be returned to the crank case. To prevent 'back firing a pipe or passage is carried from the exhaust pipe round to the side passage which latter leads the combustible element to the combustion space of the cylinder. A suitable valve is arranged at the entry oi the pipe in to the side passage so that on the suction of the piston following an exhaust, the damp remains of the products oi combustion in'tlie exhaust pipe caused by the formation of steam resulting from the rapid burning oi the'hydro-clarbons in the presence of oxygen, is drawn into the side passage and forms a layer of non combustible matter in the side passage between the cylinder' Where. burning may still be taking place and the crank case'jvhere the This layer effectually prevents the danger of back firing and mingling with the charge as it passes into the cylinder enables it to sustain a higher degree of compression giving an explosion enhanced power.

The apertu'refor the exhaust in ythe cylinder is formed in a. special way, having a narrow slit at its upper part toward the cylinder head, which is' continued for some distance and gradually widening;- the -widening becomes suddenly more pronounced until it finishes in a regular square or other opening. This is designed to produce a restricting and lengthening of the passage of the exhaust gases through the opening, diminishing their Avelocity and causing a gradual instead of the sudden expansion usually the case on opening into the atmosphere, thus a comparatively silent cxhaust is effected. A

In some cases, in thecrank case a separate chamber is provided, preferably formed by 'a bag of flexible material and in any case is limited as to expansion on its inner side (that is towards the interior of crank case) by a suitable metallic guard or division. This flexible bag is in direct communication with the cylinder by meansoi the side passage which in other circumstances opens into the crank case itself. The induction pipe is arranged to open into the cylinder at a point approximately at right angles to, but on a line with the opening of the side passage and in the piston head I form a passage following the contour of the piston for a quarter of its circumference and this passage is adapted to come into'the saine plane and open `communication with l'the before mentioned openings to the induction pipe andl to the side passage when the piston is at the top of its stroke. As the piston rises to thence to the bag when the opening is again cut off by the piston on its descent until it is opened by the piston head clearing it when the bag is deiated and the charge expelled to the cylinder.

In the accompanying drawings;-Fig`ure l. is a vertical section of the engine looking from the iront. Fig. 2. is a vertical section taken at right angles to Fig. l. Fig. 2 is a horizontal sectional view on the line x-Jy of Fig. 2. Fig. 3. is a similar view with the piston at the bottom of its stroke. Fig. 4. is an elevation of the exhaust opening showing its special shape. Fig. 5. is a vertical section of the engine constructed with the liexible division of the crank case. Fig. 6. is a vertical section taken at right angles thereto. Fig. 7. is a horizontal sectional plan on line a-b of Fig. 6. I

In the construction shown at Figs. l, 2, 3, and 4, Ais the cylinder, B is thc piston with usual defiectb and C is the crank case; the combustible material is drawn into the lcrank case at c, the intake being controlled by avalve in the usual manner. From the crank case Cthe side passage D communicates with the cylinder A and the combustible material passes to the cylinder from Vso side passage draws the charge into the latter and the crank case through this passage under impulse from the piston in the manner common to this type of motor. The passage for returning portions of the gases from the cylinder tothe crank case when working at less than full power is aranged from the cylinder head by the pipe EVv controlled by the valve c1 operated from" the handle bar or other convenient part. The'pipe E passes down and opens direct into the crank case as clearly seen at Fig. 2. This arrangement enables a con-- sidera'ble saving in uel'to be eected as before stated t From the cylinder' A, exhaust takes place by a pipe F ending in the usual silencer; the aperture G in the cylin der leading ,tothe pipe however is formed in a special manner having a narrow slitgl at its upper part,

tinuing some distance and gradually giyieninguntilit suddenly opens out into a regular sqiire or 'other lower part g2g As stated this eects a gradual release of the exhaust gases and is found to efectually reduce the resultingy noise following .the Lexpansion of the gases on opening into the atmosphere.

From the exhaust pipe F a pipe H is carriedl round I to the side passagel D providin/g it at its entryinto theyY passagewith a ball or other valve Irl (as shownin Fig. 2A) for opening or closingthe pipe according to the impulse from the piston. 'I h'is pipe upon suction from the -pisi ton carries the vapor ormedrin the pipe F by the exhaust to the side passage D formingin that passage a layer of incombustible matter which entirely prevents back firing, and which, mingling 'with the charge as in passes to the piston 'enables on explosion enhancedpower to be obtained due to the formation of steam in the cylinder.

In the arrangement shown at Figs. f5, 6, and 7, the crank case C is divided and on oneside is arranged a flexible compartment J which is 'limited on its inner side by a metal or other guardl. This flexible bag or,

compartment is secured at its upper end inthe lower part of the side'passage D so that the only communication the passage has withthe crank case is with-the bag. The induction pipe for the petroleum vapor or other' combustible is arranged to enter the cylinder'at K, the opening of the pipe being on a line with the opening of the passageD.' For providinga means of communica tion between the two, so that the charge mayA pass into D, the piston B -is'formed with a port L extending for quarter oi its innencontour or other distance corresponding to the' relative positions o'ffthe, port K 'and opening of passage D. By this arrangement, when the piston is at the top of itsstroke, lthe two passages are placed `in communication and the charge 'drawn into the bag'or. compartment .T from-which it is expelled and v'passes Vto the cylinder on the descent of the piston as already ell,- plained. In this case the return E from the cylinder andthe pipe H ,frm' the exhaust pipe' F and the other partsare as in the case illustrated at Figs, 1, 2, and 3, except that the pipe communicates withithe bag J instead of the crank case proper.: It` will be seen that the iig, means for drawing ,the damp remains from the exvflexible 'compartment enables meto dispense with the usual induction valve while theproper charge is drawn into this compartment by the portl in the piston and is regulated by the size of that port.

The illustrations and the foregoing descriptions refer only toa-motor with a single iy wheel'and bearing on one side only but the invention is ot course equally ap plicableto amotor with two as it would only be necessary to provide the division of the crank chamber stout enough to carry the bearing:

Whatlclaim then isz- 1."ln an internal combustion engine, having a casing,v,a

cylinder, and van' exhaust pipe from the latter, u supply .passage communicating with .said cylinder and said cashaust pipe and for preventing back firing, and comprising a passage provided with a valve and connecting the rstnamed passage with said exhaust pipe, in combination with separate means for returning fuel from the cylinder to the crank casing when working at less than full power i und thereby varying the charge in said cylinder and theA Aexhaust through s aid pipe.

2. In nninternal combustion -engine having a' 'crank casing, a cylinder and an exhaust pipe from the latter,

'in said casing for operating said'piston, a supply passage from Vthe casing to the cylinder and for 4registering with the port in the piston, and means for drawing the damp remainsfrom-,the exhaustpipe and for preventing back irlng`,"` and comprising a passage with which the port ot 'the piston is brought into register'and'which is provided with a valve and connecting the first-named passage with the exhaust pipe.

' 4. vIn an internal combustion engine having n crank cas@ ing, 'u cylinder, and an exhaust pipefrom the latter, 'means for supplying fuel to said casing, a supply passage communlcating with said cylinder, and said casing, andiineans for returning non-combustible matter trom said exhaust pipe to said supply passage. v 5. In an internal combustionenglne, a crank casing hav# ing a flexible compartment, a cylinder, and an exhai'st pipe from the latterrin combination'with a'supplypassage communicating with saidv cylinder and said iiexible compari?? kment, and meansfor returning non-combustiblematter ,'i'rom said exhaust pipe to said supply passage.

- 6. In-anjinternal combustion engines casing, a cylin-' dei', nnfexha'ust aperturefrom the latter and having a slit gradually widened .and becoming suddenly more pronounced, an exhaust pipeconnected with said aperture, a supply passage leading' to the cylinder, and means for returning-non-combustible matter from'saidl exhaust pipe to said supply passage.

in testimony whereof,l I have signed-.my name to' this 'specidcationin the presence ot two subscrihingewitnesses, 

